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    <title>Document</title>
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<body>
    <script>
        const select = document.querySelector('select')
        fetch('http://ajax-api.itheima.net/api/province')
            .then(res => res.json())
            .then(res => {
                console.log(res)
                return Promise.all(res.data.map((el) => {
                    return fetch(`http://ajax-api.itheima.net/api/city?pname=${el}`)
                        .then(res => res.json())
                        .then(res => {
                            console.log(res)
                            return Promise.all(res.data.map((el) => {
                                return fetch(`http://ajax-api.itheima.net/api/area?cname=${el}`)
                                    .then(res => res.json())
                            }))
                        })
                }))
            })
            .then(res => {
                console.log(res)
            })
    </script>
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